*{
    margin: 0;
    padding: 0;
    font-family: "Microsoft Yahei";
}
body{
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}
a{
    color: #000;
    text-decoration: none;
}

/*导航栏*/
nav{
    width: 100%;
    height: 60px;
    background: #000;
    line-height: 60px;
}
/*logo*/
nav>img{
    width: 150px;
    height: 60px;
    margin-left: 40px;
}
#usermsg{
    float: right;
}
/*用户头像*/
#usericon{
    vertical-align: middle;
    margin-right: 20px;
    border-radius: 50%;
    border: 2px solid #999;
    cursor: pointer;
}

/*二级分类*/
/*二级分类导航*/
.content{
    width: 100%;
    height: auto;
    flex: 1;
}
.resnav{
    width: 85%;
    height: auto;
    margin: 0 auto;
    font-size: 14px;
}
.resst,.resnd,.level{
    width: 100%;
    height: auto;
    border-bottom: 1px solid #ccc;
    padding: 0 10px;
}
.level{
    border: none;
}
.resst div,.resnd div,.level div{
    width: 91%;
    height: auto;
    display: inline-block;
    box-sizing: border-box;
}
.resst>span:nth-child(1),.resnd>span:nth-child(1),.level>span:nth-child(1){
    font-weight: 600;
    vertical-align: top;
    cursor: auto;
}
.resst span,.resnd span,.level span{
    display: inline-block;
    margin-left: 50px;
    margin: 20px;
    cursor: pointer;
    padding: 7px 12px;
    border-radius: 5px;
}
.cli{
    color: #fff;
    background: #2b333b;
}
/*二级分类内容*/
.rescon{
    width: 100%;
    height: auto;
    background: #f3f5f7;
    padding: 30px 0;
}
.rescon>div{
    width: 85%;
    height: auto;
    margin: 5px auto;
    overflow: hidden;/*使用float会让rescon里面的div脱离文档流，加上这个属性就好了*/
}
.course{
    width: 20%;
    height: 240px;
    float: left;
    margin-bottom: 10px;
    position: relative;
    padding: 10px;
    box-sizing: border-box;
}
.rescon_top{
    width: 100%;
    height: 20%;
    border-radius: 5px 5px 0 0;
    background: lightblue;
}
.rescon_top>div{
    height: 44px;
    line-height: 44px;
    margin: 0 auto;
    color: #fff;
    font-size: 15px;
    padding: 0 10px;
    box-sizing: border-box;
}
.iconfont{
    font-size: 23px;
}
.icon-aixin{
    position: absolute;
    right: 20px;
    z-index: 12;
    font-size: 25px;
    cursor: pointer;
}

.course a{
    height: 80%;
    display: block;
    margin: 0 auto;
    border-radius: 5px;
    box-shadow: 1px 5px 15px #999;
    transition: all 0.3s linear;
    border-radius: 0 0 10px 10px;
    cursor: pointer;
}
.course a:hover{
    box-shadow: 4px 6px 12px #999;
    transition: all 0.3s linear;
}
.rescon_bot{
    width: 100%;
    height: 100%;
    border-radius: 0 0 10px 10px;
    background: #fff;
    position: relative;
}
.rescon_bot>div{
    width: 85%;
    margin: 0 auto;
}
.rescon_bot>div:nth-child(1){
    line-height: 50px;
    font-size: 15px;
}
.rescon_bot>div:nth-child(2){
    color: #666;
    font-size: 14px;
    line-height: 28px;
    max-height: 90px;
    overflow: hidden;
}
.rescon_bot>div:nth-child(3){
    color: #666;
    font-size: 14px;
    text-align: right;
    position: absolute;
    right: 10px;
    bottom: 10px;
}

/*分页*/
.pages{
    width: 100%;
    font-size: 13px;
    text-align: center;
    color: #666;
    line-height: 30px;
}
.pages>span,.page{
    cursor: pointer;
    margin: 0 5px;
    display: inline-block;
    height: 30px;
}
.page{
    width: 30px;
}
.pagehover{
    width: 30px;
    height: 30px;
    background: rgba(0,0,0,0.1);
    border-radius: 50%;
    transition: background 0.2s ease-in;
}
.pages>span:nth-child(1),.pages>span:nth-child(2){
    color: #ccc;
    width: auto;
    cursor: auto;
}
.pagescir{
    background: #333;
    border-radius: 50%;
    line-height: 30px;
    color: #fff;
}

/*版权信息*/
footer{
    width: 100%;
    height: 80px;
    background: black;
    margin-top: 70px;
    color: #fff;
    line-height: 80px;
    text-align: center;
    font-size: 14px;
}